金刚石串珠绳耐用度经验公式的实验研究

为了实现海底石油管道切割作业,采用均匀设计方法对水下金刚石绳锯串珠绳的耐用度进行了试验研究.使用MINITAB软件,建立了主要工艺参数对耐磨损率的多元线性回归方程,进行了回归分析,求得了绳锯耐磨损率较为精确的经验公式.进一步探讨了水下金刚石绳锯耐磨损率的工艺规律,为满足绳锯机设计要求,优化工艺参数提供了理论依据.     

单层输油管道切割试验

利用金刚石串珠绳切割单层输油管道的试验条件,分析了单层输油管道的结构特点和串珠绳切割管道钢管部分的面积和切口宽度变化规律。通过对单层输油管道切割试验验证了采用金刚石串珠绳切割单层输油管道的可行性,测定了绳锯机的工作效率,考察了设备工作稳定性,观测了液压系统的工作状况,明确了金刚石串珠绳切割单层输油管道的操作规程。通过相关技术参数的检测和分析,找到了合理的切割工艺参数,客观评价了串珠绳的使用情况。     

海底石油管道切割绳锯机的设计及其试验研究

介绍了用于切割海底石油管道的金刚石串珠绳锯机组成和工作原理;进行了串珠绳锯机主要装置的结构设计;对串珠绳锯机的液压动力系统的技术参数进行了计算和确定。通过金刚石绳锯机切割海底石油管道的试验,对记录数据分析后得到了串珠绳锯切向切削力与进给速度、串珠绳的耐磨损率与切削速度、串珠绳的耐磨损率与进给速度等之间的关系。得出了用金刚石串珠绳锯机切割海底石油管道是行之有效的切割方法这样的结论。     

Cutting force and tool wear of single diamond-coated bead

The aim of this study is to optimize stone materials cutting by diamond wire cutter. Attention is focused on the study of the cutting process through sintered diamond-encrusted beads used to work granite. This study is aimed at understanding the interaction between the bead and the material; in detail, experimental equipment was designed to test individual diamond-coated beads, and it was installed on a numerical-control work center. This equipment made it possible to test an individual bead and, in particular, to determine its cutting power and its main force components on the basis of various process parameters, such as cutting velocity (V _t) and feed velocity (V _a). The test runs also made it possible to determine wear on each bead on the basis of process parameters. This is a necessary first step to be able, in the future, to optimize the tool and the cutting process.     

金刚石串珠绳的磨削与磨损机理

介绍了金刚石串珠绳的结构和类型。结合海底石油管道切割试验研究了金刚石串珠绳的磨削机理,分析了金刚石串珠绳微观磨损形态和特性;通过对磨削后的串珠表面形貌显微照片的观察,验证了分析结果的正确性。针对海底油气管道切割定量分析了串珠的磨损过程和规律,得到了串珠绳的耐磨损率与进给速度、串珠绳的耐磨损率与切削速度的关系曲线。分析了串珠绳磨削加工表面质量。     

锯切花岗石过程中金刚石串珠的磨损特性

通过跟踪烧结式金刚石绳锯切割花岗石过程中串珠直径磨损及串珠表面金刚石磨粒的磨损,研究串珠的磨损规律,并建立金刚石串珠的磨损模型。进行金刚石绳锯切割花岗石试验,试验结果表明,在金刚石串珠锯切过程中,单颗串珠沿其轴向出现不均匀磨损。串珠前端的磨损量会明显大于串珠中、后端磨损量,串珠后端的磨损也略大于串珠中端的磨损,串珠呈现腰鼓状磨损;串珠前端金刚石磨粒的平均出露高度高于串珠中、后端的磨粒平均出露高度,但在岩屑的磨蚀作用下,串珠前端的高出露金刚石磨粒容易产生非正常脱落。串珠磨损可分为腰鼓形状成形及腰鼓形状保持两个阶段。在切削负荷及岩屑磨蚀的共同作用下,串珠前、中、后三个部分在两个阶段的磨损表现各不相同。串珠前端是以岩屑磨蚀为主,而对于串珠中端,则是主要承受切削负荷。串珠后端两种作用的影响程度相对较弱。     

便携式小冲杆试验微损取样装置的设计

小冲杆试验是一种对微型试样进行检测评价的方法,对在役设备的质量检测和剩余寿命预估具有重要作用。设计了一种应用于小冲杆试验的微损取样装置,并对取样的工艺路线进行了研究,主要包含安装定位、切割槽的加工、金刚石线锯切割以及刷漆修复等步骤。其中,砂轮机用于在设备表面加工切割槽,金刚石线锯切割机用于将微型试样取下。着重研究了金刚石线锯切割机中的张紧机构和摇摆机构,保证恒张力切割的同时提高了切割效率,充分发挥了线锯切割的优越性。这种取样装置体积小、重量轻,满足便携式的要求,能够适应多种环境下的微损取样。     

金刚石串珠锯锯切工艺及磨损机理研究

在锯切试验基础上 ,研究了金刚石串珠锯锯切速度、进给速度与串珠绳磨损率、锯切力之间的关系 ,分析了金刚石串珠锯的磨损机理 ,并对实际锯切加工提出了建议。     

Development of an electrolyte jet type apparatus for manufacturing electroplated diamond wires

Multi-wire sawing with a fixed diamond wire is widely used for the mass production of wafers. In this study, a novel electrolyte jet type electroplating method was devised to improve the productivity of these wires. The method is based on increasing the limiting current density (LCD) in the electroplating unit. First, an electrolyte jet type electroplating unit was designed, and the plating characteristics were investigated. To increase the LCD during plating process, the method of decreasing the depletion layer of nickel ions around the core wire was approached. The experimental results indicated that the LCD can be increased by increasing the flow rate of the electrolyte. Next, the influences of composite plating conditions on the state of abrasive distribution and density of the diamond wires were experimentally verified, and the process of selecting the optimal fabricating conditions was clarified. Lastly, the cutting performance of the prototype diamond wires was verified by slicing a polycrystalline silicon ingot. The relationship between the surface roughness of the sliced wafers and the abrasive density of the diamond wires was studied.     

Sawing performance comparison of brazed and sintered diamond wires

Great attention has been paid on fabricating diamond wire by using the brazing diamond because of its strong chemical bonding strength and controllability of grits distribution. Although several serving performances of brazed diamond wire have been reported, seldom do these studies refer to its process characteristics. Sawing performances of a brazed diamond wire are investigated and compared with those of a sintered diamond wire on a wire saw machine. The surface topographies of beads selected from the two wires are micro observed before sawing. The sawing tests are carried out in constant feed rate feeding(CFF) and constant normal force feeding(CNFF). In CFF test, sawing force, power, and the cut depths of positions on contact curve are measured. Then, coupled with the observations of beads topographies, sawing force and its ratio, relations of power against material removal rate, and contact curve linearity are compared and discussed. In CNFF test, the sawing rates of the two wires are investigated. The results indicate that the brazed wire performs with lower sawing force(less 16% of tangential force and 28% of normal force), more energy efficiency(nearly one-fifth of sawing power is saved), at a higher sawing rate (the rate is doubled) and with better contact curve linearity as compared with the sintered wire. This proposed research experimentally evaluates the sawing performances of brazed diamond wire from the aspect of process parameters, which can provide a basis for popularizing the brazed diamond wire.     

Research on electrochemical discharge-assisted diamond wire cutting of insulating ceramics

Insulating ceramics are difficult to cut because of their high hardness and brittleness properties. This research proposes an electrochemical discharge-assisted diamond wire method for cutting insulating ceramics. The high temperature generated from electrochemical discharge facilitates the spalling of ceramics by the moving diamond wire. Experimental results showed that the material removal rate (MRR) of the new cutting method increased compared with the conventional diamond wire cutting process. Besides, electrochemical discharge had limited influence on the surface roughness and the wear of diamond wire. Additionally, the influence of the process parameters (DC voltage, wire speed, and counterweight mass) on the MRR and surface roughness was analyzed through experiments. The results showed that the MRR and surface roughness initially increased and then decreased with the increasing DC voltage; however, the variation was little. The higher wire speed resulted in an increased MRR and had little influence on the surface roughness. The MRR and surface roughness increased with the increasing counterweight mass.     

双尖角磁场再压缩等离子弧切割

通过对于双尖角磁场再压缩等离子弧的电弧形态、电特性、热特性、力学特性及电弧稳定性的测定与分析,说明采用双尖角磁场再压缩等离子弧沿电弧截面长径方向进行切割是提高切口质量、工艺稳定性和切割生产率的有效途径。本文介绍了采用此方法对16～20mmlCr18Ni9Ti钢板切割的试验结果,并就双尖角磁场的磁头结构、再压缩等离子弧的物理特征及工艺特性、切割规范选择以及切口质量进行了探讨。     

环形电镀金刚石线锯的研制

研制了一种新型环形电镀金刚石线锯 ,介绍了锯丝基体的制备及锯丝电镀工艺。锯切试验表明该金刚石线锯具有锯切表面质量好、锯切效率高、出材率高等优良性能 ,尤其适合贵重硬脆材料以及各向异性复合材料的切割加工。     

电火花线切割技术发展动态分析

随着机械行业的飞速发展,对各类电火花线切割机床的需求量不断提高,市场竞争日趋激烈.这种形势刺激了相关厂商加大对相关技术的研究力度,促进了对电火花线切割机床性能及功能的提升,实现了电火花线切割技术的进一步发展.     

线切割机床加工铝件电极丝进电装置研究

针对普通线切割机床加工铝件常出现的问题,对普通线切割机床加工铝件的切割过程特性进行了研究.对普通线切割机床加工铝件时产生的Al2O3损坏机床电极丝进电装置导电块的避免方案进行了分析,提出了取消普通线切割机床电极丝进电装置导电块,重新设计普通线切割机床电极丝进电装置的方案.为提高切割效率,进电位置选在了两前导轮轴处;为避免在导轮轴处产生火花放电,腐蚀导轮,影响导轮寿命,对导轮结构进行改进,选择了加长导轮轴;为不影响导轮的运转,选择用石墨与轴接触,达到既能导电,同时还能自润滑以提高寿命.研究结果表明,改进后的普通线切割机床,在切割铝件时,可避免导电块的损坏问题,降低断丝、短路的机率,提高被切割铝件的表面质量.     

基于ANSYS/LS-DYNA的单颗粒金刚石切割氧化铝陶瓷表面温度场研究

对单颗粒金刚石切割氧化铝陶瓷过程中切削热、表面粗糙度、应变进行研究,通过利用ANSYS/LS-DYNA对切削过程进行3D模拟,热力耦合,分析在不同走丝速度条件下,工件表面裂纹和形貌情况;将切削温度场拟合进切削过程,研究切削热分布以及切削过程中应变问题。仿真结果显示,切削热基本维持在60℃左右,且温度传导较慢,范围较小;工件在切削过程中与磨粒底部接触的裂纹深于两侧,且受走丝速度影响较小;脆性材料切削主要以弹性应变为主。     

激光切割CVD金刚石厚膜的工艺研究

本文利用Nd:YAG激光器对0.4mm厚的CVD金刚石膜进行切割,用扫描电子显微镜(SEM)研究了激光脉冲能量、脉冲宽度和脉冲频率等工艺参数对金刚石厚膜切割的影响。研究结果表明,在脉冲电流高于200A和减小脉冲电流至150A、脉冲宽度为2ms时能一次性切透金刚石厚膜但切割断面存在许多微裂纹和缺陷。增大脉冲频率有利于提高切割断面的平整度;采用二次切割比一次切割可得到更为平整的切割断面,断面粗糙度Ra可达到1μm。     

基于正交实验金刚石工具耐磨损性研究

本实验研究的目的是通过不同的加工参数,对热压成型的金刚石工具磨损量影响的分析,进而确定较理想的加工参数,实现高效率的加工。实验采用LK6090CNC机床加工石材。通过正交实验的设计方法,并制定不同的加工参数,工具的磨损量应用高精密电子天平测得。实验数据表明,对金刚石工具磨损量影响的主要参数是切削深度,其次是进给速度,最后是主轴转速。工具底面磨损比侧面严重,底面磨损主要以脱落为主,侧面主要以冲击破碎为主。     

车床式泡沫塑料切割台设计与实现

车床式泡沫塑料切割台,其外形结构与车床相似。在泡沫坯体夹具和切割刀夹具以及引电机构共同作用下,用电热丝刀具切割泡沫材料。刀架承载着切割刀能在垂直于XZ和YZ平面方向上作旋转切割,也能在横向和纵向方向上作平面切割,还能调整刀架角度作斜面切割。由于有尺寸定位机构和走刀量的控制机构,使得切割过程能按设定的尺寸准确加工,产品表面光滑平整。毛坯夹具带有锁紧机构,能控制毛坯在YZ平面上作任意角度旋转。设备采用的刀具有不同种类,分为旋转切割刀、平面切割刀以及阶梯孔切割刀,以方便切割不同结构的泡沫制品。     

多参数金刚石圆锯片锯切性能试验机的研制

专门研制出一种多参数的试验机,用以检测石材加工所用的金刚石圆锯片的锋利度、耐磨性等锯切性能。简介了该试验机的系统组成,具体指出了用来衡量金刚石圆锯片的锯切性能的锯切功率、锯切阻力、锯片转速、给进速度和噪声等多种参数的检测和控制工作原理,给出了基于LabVIEW的锯切参量检测程序设计面板和噪声检测程序代码。该系统测控操作简便,具有很强的适应性,满足综合评价金刚石圆锯片锯切性能的基本要求。